Crusher lining



L. R. M LEOD CRUSHER LINING June 20, 1961 Filed Feb. 18, 1959 INVENTOR LESTER R. MOCLEOD f Q m f M ATTORNEYS United States Patent 2,989,253 CRUSHIER LINING Lester R. MacLeod, Prescott, Ariz. (Box 13, Chino Valley, Ariz.) Filed Feb. 18, 1959, Ser. No. 794,053 3 Claims. (Cl. 241-294) This invention relates to linings for large gyratory crushers and, more specifically, to linings constructed of tiersof concaves of the type having lip portions formed on their lower edges to facilitate their removal. In particular, the invention is directed to improvements in such linings by which support is provided for the lip portions of the concaves of the lowermost tier both during the operation of the crusher and the removal of the concaves.

It is conventional practice in lining gyratory crushers to lay concaves in circumferential tiers over the entire working surface of the substantially conical crusher shell and to pour molten zinc into spaces between the concaves and the shell where it can solidifyto bond the concaves securely in place. One undesirable effect of this otherwise satisfactory practice is that when the concaves become worn and are in need of replacement they can only be removed from the shell by breaking the tight zincsoldered bond. This was an operation which previously required the use of a cutting torch and many hours of ditficult labor. However, recent advances in concave design have considerably reduced the great amount of effort and time involved in removing linings after they had become worn by making available concaves having a transverse downwardly projecting lip portion on their lower edge which provides a surface against which a prying force may be exerted. It is usually possible to remove these newer concaves simply by hooking a pry bar under their lip portions and hoisting up on the end of the bar so that the concave is wrenched from the shell.

However, there are certain critical disadvantages in concavesof this type which definitely limit their efiectiveness when they are used in the lowermost tier of concaves in the crusher. As is generally known, the concaves in the lowermost tier are subjected to severe crushing forces during the operation of the crusher because at that point the material is broken into the smallest pieces. Hence, the lip portions become worn thin to such an extent that they are considerably weakened. This sometimes enables the lip portions to break oif during the operation of the crusher, since in the lowermost tier they are not supported by any underlying portions of an adjoining tier as is usually the case with the lip portions in the higher tiers. Moreover, when the prying force is applied to the lip portions of the concaves of the lowerm'ost tier to remove them, the weakened lip portions break off in many instances before the concave can be pulled free from the shell. This occurs most often when thc first key" concave is pulled from the tier.

It is the purpose of the present invention, therefore, to improve upon concaves of the type described to insure that the lip portions of the concaves in the lowermost tier do not break olf either during the operation of the crusher or the removal of the concaves. This purpose is achieved by incorporating supporting means both in the shell of the crusher and in the concaves themselves which act together to strengthen the lip portions. At the same time, the invention aims to achieve this support of the lip portions without in any way interfering with the application of the prying force thereto during the removal of the concaves.

The invention contemplates improvements in gyratory crushers of the type which includes a shell lined interior- 1y with a plurality of tiers of concaves and wherein the concaves of at least the lowermost tier each have transverse downwardly projecting lip portions on the lower edge thereof spaced from the shell to provide a surface against which a prying force may be exerted to remove the concave. Generally stated, the improvements comprise a ring member positioned coaxially within the shell substantially in the plane of the lower edge of the lowermost tier of concaves. The lip portions of the concaves of the lowermost tier overlie and are spaced from the inner circumference of the ring member. Rib means are included in the lip portions of each of the concaves of the lowermost tier in abutment with this ring member. The rib means are spaced apart circumferentially on each concave to define recesses adapted to receive a tool for exerting the prying force on the lip portion of the concave. By this construction, the rib means provide support for their associated lip portions both during the operation of the crusher and during the removal of the concaves.

Preferred embodiments of the invention are described hereinbelow with reference to the accompanying drawing, wherein FIG. 1 is a fragmentary longitudinal section of a gyratory crusher lined according to the invention;

FIG. 2 is a perspective view of one of the concaves of the lowermost tier in the crusher of FIG. 1 looking toward its backside;

FIG. 3 is a fragmentary longitudinal section of the lower edge of the lowermost tier of one of the new concaves laid in place against the shell of the crusher; and

FIG. 4 is a section taken along the line 44 of FIG. 3.

Referring first to FIG. 1, the lower portion of a substantially conical shell 10 of a gyratory crusher is shown in which a gyratory eccentric 11 is mounted in the usual manner. The shell 10 is constructed of a plurality of heavy steel annular segments 13 which are bolted or otherwise secured together. In FIG. 1, the segment 13 shown is that which defines the constricted lower portion of the crusher adjacent the discharge end where the finest crushing is accomplished by the eccentric 11. Beneath the segment 13, a similar segment 14 is secured which forms the discharge end of the apparatus through which the material passes after it has been crushed.

The entire interior working surface of the shell 10 is lined by a plurality of circumferential tiers 16, 17, 18 etc. of concaves which provide a hardened working surface against which the material is crushed. It is common practice to provide pads 20 on the backside of the concaves in each tier so that a space communicating from tier to tier is defined between the concaves and the shell 10 which may be filled with the molten zinc 21 or other low melting point metal. Shallow cavities 23 are also formed in the backside of the concaves which are filled with cement 24 before the concaves are laid in order to minimize the amount of zinc required. By these means, a firm backing is provided for all the tiers of concaves and each concave is securely bonded to the shell 10.

In the lowermost tier 16, the concaves are of special construction as provided by the invention. In FIG. 2, a concave 26 taken from the lowermost tier 16 is shown. It includes a heavy plate portion 28 having a substantially smooth working surface on its frontside which is opposed to the eccentric 11 at the narrow lower end of the shell. The backside of the plate portion 28 has a plurality of cavities 29 defined therein which can be filled with cement as described above. Also, pads 31 and 32 are formed on the backside of the plate portion 28 at the upper and lower edges thereof respectively to abut the inside surface of the shell 10 when the concave is laid in place.

The upper pad 31 does not extend continuously across the upper edge of the concaves 26 but has a cut-out portion 33 formed therein to permit molten zinc to be passed into the spaces behind all of the concaves. It will be noted that the lower pad 32 extends continuously across the lower edge. of the concave and prevents the molten zinc from escaping when it flows down behind the concaves in the lowermost tier 16. A shoulder 35 preferably is formed in the upper edge of the concave 26 to receive the downwardly extending lip portions on the concaves in the tier 17 above.

Turning now particularly to FIGS. 3 and 4, at the lower edge of the concave 26 a transverse lip portion 36 is formed which projects downwardly from the plate portion 28. The backside of the lip portion 36 provides a surface 37 against which the prying force may be exerted to remove the concave after it has become worn. For this purpose, a pry-bar of any suitable design, indicated at 38 in dotted lines, may be hooked behind the lip portion 36 with its tip contacting the surface 37 to permit the lower end of the concave 26 to be pulled from the shell 10. It is this lip portion 36 which is generally most severely worn by the crushing forces and which is often broken during the operation of the crusher or when it was pulled outwardly by thepry-bar 38.

According to the invention, therefore, integral ribs 40 are included in the concaves 26 which extend rearwardly from the backside of the lipportion 36 and downwardly from the lower edge of the plate portion 28. These ribs considerably reinforce the lip portion 36 to permit it to withstand much greater inward and outward radial forces without failing. In the embodiment shown, the concave 26 includes three ribs 40, though more or fewer could be provided. They are spaced apart circumferentially to provide access for the pry-bar 38 as seen in FIG. 4.

To insure that the ribs 40 are firmly supported, a ring member 42 of rectangular cross section is provided in the shell 10. It fits coaxially in the shell in a groove defined by a shoulder 43 in the segment 14, and is securely held thereby substantially in the plane of the lip portions of the lowermost tier 16 of concaves. The inner surface of the ring member 42 is substantially cylindrical and provides a flat abutting surface for the ribs 40. Also, the ring member 42 extends radially inwardly somewhat from its groove into the interior of the crusher to provide a small shoulder 45 which is adapted to locate the lowermost edge of the pad 32 of the-concave 26. If desired, the ring member can be made in one or more pieces or even formed as an integral part of the crusher shell.

By this construction, the ribs 40 in conjunction with the ring member 42 support the lip portions 36 during the operation of the crusher against radially outward crushing forces which would tend to break off the lip portion 36. Also, when the pry-bar 38 is hooked under the lip portion 36 to pull the concave 26 from the shell, the rib 40 adds considerably to the strength of the lip portion to prevent it from being broken in its worn condition by the radially inward force exerted upon it by the pry-bar. At the same time, the ribs 40 are spaced circumferentially alongthe backside of the lip portion 36 to provide ample prying surface 37 against which the tip of the pry-bar may be applied to remove the concaves.

I claim:

1. In a gyratory crusher which includes a substantially conical shell lined interiorly with a plurality of circumferential tiers of concaves and wherein the concaves of at least the lowermost tier each have a transverse downwardly projecting lip portion on the lower edge thereof spaced from said shell to provide a surface against which a prying force may be exerted to remove the concave,

the improvement which comprises a ring member secured coaxially to the interior of said shell substantially in the plane of the lower edge of the lowermost tier of concaves, the lip portions of the concaves of said lowermost tier overlying and being spaced from the inner circumference of said ring member, and rib means included in the lip portion of each of the concaves of said lowermost tier in abutment with said ring member, said rib means being spaced apart circumferentially on each concave to define recesses adapted to receive a tool for exerting said prying force, whereby said rib means provide support for their associated lip portions both during the operation of said crusher and the removal of said concaves.

2. In a gyratory crusher which includes a substantially conical shell lined interiorly with a plurality of circumferential tiers of concaves each having a transverse downwardly projecting lip portion on the lower edge thereof spaced from said shell to provide a surface against which a prying force may be exerted to remove the concave, the improvement which comprises a ring member having a substantially cylindrical inner circumferential surface secured coaxially to the interior of said shell substantially in the plane of the lower edge of the lowermost tier of concaves, the lip portions of the concaves of said lowermost tier overlying and being spaced from the inner circumferential surface of said ring member, and rib means located behind and integral with the lip portions of each of the concaves of said lowermost tier in abutment with said ring member, said rib means being spaced circumferentially on each concave to define recesses adapted to receive a tool for exerting said prying force on the lip portion, whereby said rib means provide a support for their associated lip portions both during the operation of said crusher and the removal of said concaves.

3. In a gyratory crusher which includes a substantially conical shell lined interiorly with a plurality of circumferential tiers of concaves each having a transverse downwardly projecting lip portion on the lower edge thereof spaced from said shell to provide a surface against which a prying force may be exerted to remove the concave,,the improvement which comprises a ring member secured coaxially within an annular groove formed in the interior of said shell, said ring member having a substantially cylindrical inner circumferential surface exposed within said shell substantially in the plane of the lower edge of the lowermost tier of concaves, the lip portions of the concaves of said lowermost tier overlying and being spaced a uniform distance from the inner circumferential surface of said ring member, and ribs located behind and integral with the lip portions of each of the concaves of said lowermost tiers in abutment with said ring member, each of said ribs extending radially outwardly from the,

References Cited in the file of this patent UNITED STATES PATENTS 720,853 Spargo Feb. 17, 1903 1,110,887 Capen Sept. 15, 1914 2,813,685 MacLeod Nov. 19, 1957 

